public class Main {

    public static void main(String[] args) {
        System.out.println("Hello World!");

        String serverCode = "AE9CH4";
        String clientCode = "ae9ch4";

        if (clientCode.equalsIgnoreCase(serverCode)) {
            System.out.println("ok");
        } else {
            System.out.println("fail");
        }
    }
}
